Wireless data traffic has explosively increased due to invigoration of a wireless multimedia service and a Social Networking Service (SNS) according to the spread of smart phone use and the expansion of wireless demands, such as Machine To Machine communication. Accordingly, a big data environment which is not easy to process through data transmission methods of the related art is imminent.
With the advent of the big data environment, a Massive Multiple-Input Multiple-Output (M-MIMO) system is being considered for efficiently managing wireless resources. Further, the M-MIMO system is being spotlighted as an energy efficient green communication technology.
Studies on the wireless communication system of the related art have been focused on the increase in a channel capacity, such as installation of more base stations or securing of a frequency band. For example, technologies of the related art including Orthogonal Frequency Division Multiple Access (OFDMA), a multi-antenna system, and a relay transmission system attempt to provide a high channel capacity.
However, high energy consumption is inevitably required to provide the high channel capacity. Considering that, the method for raising the channel capacity is not efficient for devices with restricted total energy or networks focused on energy efficiency.
Meanwhile, with the advent of the M-MIMO system and the distributed antenna system, it is easier, in recent years, to satisfy transmission requirements of a mobile station based on abundant resources. Accordingly, a wireless communication system is required which is maximally energy efficient and satisfies the transmission requirements of the mobile station.
In the case of transmission techniques of the related art considering energy efficiency, a plurality of antennas are used so that transmission power but not power consumption is considered. However, due to the advent of the M-MIMO system, more power should be consumed to operate so many antennas.
Therefore, a need exists for a signal transmission method for satisfying a user's transmission requirements and improving power efficiency of a base station based on power consumption in a Radio Frequency (RF) circuit as well as transmission power.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.